CHAPEL HILL -- The category “adversity in a game setting” can be checked off the North Carolina preseason itinerary.

Shaw, a Division II program, posed plenty of problems and held a surprising lead with less than 15 minutes remaining until the Tar Heels broke away for an 81-54 victory in exhibition basketball Friday night at the Smith Center.

“It was a good thing for our team,” swingman Reggie Bullock said, “just to see how mentally tough we are.”

North Carolina, which debuted at No. 11 in the season’s first Associated Press Top 25 poll earlier in the day, responded by ripping off 23 consecutive second-half points to transform a 44-44 tie into the highlight-filled rout that’s expected of such a matchup.

P.J. Hairston nailed a pair of deep 3-pointers from virtually the same spot on the wing in rapid succession to kick-start what ballooned into a 28-2 run.

Brice Johnson and James Michael McAdoo thumped dunks in transition later in the surge that were generated by increased pressure.

“I think it all happened on the defensive end, with just really turning up it up and keeping it up,” McAdoo said.

McAdoo finished with 16 points and eight rebounds. Freshman big man Joel James came off the Tar Heels bench for 13 points on 6 of 7 shooting from the field and seven rebounds.

Leslie McDonald scored 12 points as a reserve for North Carolina while Johnson, a springy freshman forward, chipped in eight points and six rebounds off the bench.

It was the only exhibition game for the Tar Heels, who open the regular season Nov. 9 against Gardner-Webb. And Dexter Strickland said he never became nervous, even as Shaw rallied out of a 10-point deficit to regain the lead.

But Hairston said a distinctly urgent vibe gripped North Carolina as it huddled during the first timeout of the second half, when the Bears led 43-41.

“It was like, ‘OK, we have to tighten up right here, because if this happens, this is going to be seen everywhere,’ ” Hairston said. “It was like the team clicked.”

North Carolina coach Roy Williams tinkered with player combinations and rotations. His starting lineup consisted of freshman Marcus Paige at point guard, Bullock and Strickland on the wings and McAdoo and Desmond Hubert in the post.

McAdoo played with two stitches in his upper lip, the result of a wayward elbow from teammate Jackson Simmons in practice Thursday.